It appears that as far as UDisks2 is concerned, your system has only one optical drive. Please verify that your system can access both drives (checking for the presence of /dev/sr* entries would be a quick way of doing so, or you could put discs in both drives and see if they are both accessible).

In fact there is the presence of sr0 and sr1 but if I insert a disk in sr0 I can operate with several software like k3b, Dragon and VLC or manage it with Dolphin, while, if I insert a disk in sr1 I can only operate with Dolphin.Thank You.

I see. I suspect K3b and Dragon Player try to deal with devices (which doesn't work), while Dolphin deals with storage entries (which does work). Are the two optical drives the same make/model by any chance? I suspect you've triggered a corner case/bug in either UDisks 2 or KDE's integration with it.